This invention is generally directed to photoresponsive devices; and more specifically the present invention is directed to photoresponsive devices, comprised of organic or inorganic materials and silicone ammonium salts. The photoresponsive devices of the present invention are useful in electrostatographic imaging systems, particularly xerographic systems.
Overcoated photoresponsive devices containing protective top coatings, such as silicone resins are known. These protective coatings, have been found to be highly useful when applied to various organic and inorganic photosensitive materials, such as amorphous selenium. However, in many instances, these silicone resin overcoatings have a tendency to separate from the photoconductive material primarily because of their poor adhesion properties. While adhesive materials have been developed for permanently adherring top coatings such as silicone resins to photoreceptor devices, the coatings continue to separate over extended periods of usage. Additionally, it is important that adhesive materials be employed that possesses an electrical conductivity of sufficient value so as to maintain a zero to low residual potential in the photoresponsive device.
Abrasion resistant resins, such as organothiol siloxanes, and alkylene-alkoxy silane resins are disclosed in various prior art patents including U.S. Pat. Nos. 3,986,997, 4,177,175, 4,127,697, and 4,239,668. The organothiol siloxanes however, are known to suffer from a number of disadvantages. For example, these materials require high temperatures to achieve activation, and thus are of substantially little value for use at room temperatures. Additionally, in most instances, these siloxanes have undesirable odors. Further, compositions containing such siloxanes have undesirable high residual potentials when, for example, they are utilized in overcoated photoresponsive device. Also, the use of known amino silanes as adhesives or primers for photoresponsive devices, such as those disclosed in U.S. Pat. No. 4,127,697, can cause the formation of high residual potentials in these devices.
Accordingly, there continues to be a need for new adhesive materials, and particularly adhesive materials which can be utilized in photoresponsive devices for the purpose of bonding protective coatings, such as silicone resins, to the photoreceptor surface. Additionally, and more importantly there continues to be a need for adhesive materials which possess an electrical conductivity of certain valves, that is from about 10.sup.8 to about 10.sup.-- (ohm-cm).sup.-1 in order that a zero to low residual potential can be maintained on the photoreceptor surface.